Sharpening attachment for disk harrows



Dec. 29, 1931. F. M. CASE SHARPENING ATTACHMENT FOR DISK HARROWSOriginal Filed Sept. 15, 1926 2 Sheets-Sheet luvs/Iron F'xM/vc/s H Case.

Dec. 29, 1931. F. M. CASE SHARPENING ATTACHMENT FOR DISK HARROWSOriginal Filed Sept. 13, 1926 2 Sheets-Sheet 2 entree FRANCIS M. CASE,OFCLEVELAND HEIGHTSOHIO, ASSIG-NOIR TO OF' CLEVELAND, OHIO- PATENTOFFICE. a

omens enamels,

I V SHARPEINING Arracnnnnrron DISK minnows Application filcd September1a, 1926, Serial No. 135,070. Renewed. H es, 1931.

This invention relates to sharpening at tachments for dlsk harrows and1s more partlcularly directed-to a; sharpeningjdevlce which may besupported so as toengage the 5 disk of a harrow to sharpen the samewhile i latter is adjustably mounted so that it may be moved from onedisk to the next of any one in a line withoutremoving the sharpeningdevice from the support.

Another object of the invention is to provide sharpening device whichwhen positioned adjacent one of said disks is maintained in cutting orsharpening engagement by means of an adjustable tension member whichforms a part of the sharpening device.

Other objects of the invention are to provide a sharpening device whichmay be transferred from onegang of disks of a harrow to another gang ofdisks of" the harrow, where the convex surfaces of the disks of eachgang are opposite to'each other, by

merely removing the sharpening device from.

the support of one gang and reversing it on a supporting means ofthe'adj acent/gang' of disks. i i V A further object of the inventionresides in the provision of ameans upon the sharpening device for.positioning the .cutterwith respect to the edge of the diskxtobejs'harpened so that this cutter may be radially adjusted depending'upon the direction in which the convex 's'urfaceextends and thedirection of rotationof the disks. V j

A still further object resides in-a means '40 forwsecurely positioningand mounting the supporting means with respect to'the hub of the gangofdisks so as to prevent the sharpening device if becoming loosened,from dropping down onto the cutting edge 4 of the disks.

A With the objects above indicated and other objects hereinafterexplained in view my invention consists in the construction andcombination of elements hereinafter described and claimed.

Referring to the drawings:

Fig. l is a cross sectional view taken on line 11 of Fig. 6 showing theposition and arrangement of-the attachment with respect to the disks ofthe harrow; I

Fig. 2 is a horizontal cross sectional view on line 2-2 of Fig. 1showing the relative position of the cutter with respect to the cuttingedge of the disk with the yokein section. 3

Fig.3 is a top plan view of Fig.2showing the reversible feature of theyoke. Fig. 4 is an end'view looking toward the disk in Fig. 2.

Fig. 5 is a top plan view similar to Fig. 2

but showing the sharpening device in the position it assumes when beingtransferred from one disk toanother, the lineA-A representing theextremities of the peripheries of a. gang of disks."

Fig. 6 is a rear end view of a ang of disks showlng the supporting meansor the uide bar and the sharpening device posit oned with respect to oneof the disks. 7 j Fig. 7 is a segmentary view showing a modified form ofthe supporting and spacing arm engaging the hub of the disk.

Fig. 8 is a segmental-y view showing a. further modified form to thatshown" in Fig. 7. a

Fig. 9isa modified form of sharpening device whereby a shar ening wheelhas been substituted in place o v the cutter, and

Fig. 10 is a top plan v'iewof the arrangement'shown in Fig.9. n

In the drawings, 1 indicates one of the disks of a gang and 2 representsthe-usual hub connection between the disks 1,-these disks and hubs beingsecured togetherin any suitable means. one form of means being a squareboit extendingentirely through the hub and disks as indicated at?) inFig. 1. As shown 'in'Fig. 6, 4 indicates bearings positioned around thehubs between the end disks of the gang and extending upwardly from thesebearings 4' are arms 5adjustably mounted therein, the upper ends ofwhich are riveted to a cross bar 6 usually employed as a supportingmeans for thescrapers of the various disks. This cross bar 6, however,may be any .1

other portion of the harrow which extends achacent the peripheries ofthe disks 1.

A guide rail 7 in the form of a T rail extends parallel with the crossbar 6, the web of the T rail extending upwardly and at a slight inclinetoward the vertical central line of the disks. An arm 8, T-shaped incross section with the web extending upwardly is provided with atransverse slot 9 at one end engaging with the web of the guide rail 7and is adjustably mounted thereon and secured thereto by means of a setscrew 10 extending through an opening in the end of the arm intoengagement with the web of the guide rail 7 Directly above thetransverse slot 9 and transversely thereof is an arcuate flange or rim11 formed integral with the web of the arm 8, a cross section of whichis T- shaped. A supporting bracket 12 is provided with a right angledextension 13 through which. extends a T slot adjustably engaging thearcuate flange 11 of the arm 8. This supporting arm 12 is maintained inadjusted position by means of a set screw 13a extending through the Tslot of the right angled extension 13 and into engagement with theperiphery of the arcuate flange 11. A hook bolt 14 extends through oneof a plurality of openings 15 in the supporting arm 12. the hookedportion engaging the lower end of the cross bar 6 and is held inengagement therewith by means of a nut engagingthe screw threaded endeXt-endin g beyond the supporting arm 12.

The opposite end of the arm 8 extends at a downward angle and inwardlytoward the horizontal center of the disks and has slidably mountedthereon a bracket 16 which is provided with a T slot adapted to engagethe T head of the arm 8. A depending arm 17 is formed integral with thebracket 16 and et-rtends downwardly and under a portion of the hub 3.The bracket 16 on the arm 8 is ad. justably secured through a set screw18 eX tending through the bracket 16 into the slot and into engagement:with the head of the arm 8. VBy this adjustment the guide rod 7 may besecurely and correctly positioned with respect to the peripheries of thedisks 1 so that the sharpening device is correctly position'ed along thecutting edge of the disk 1 while the same is being sharpened.

It is sometimes desirableto prevent the possibility of the arm 8 beingpulled away from the hub 3 and in such a case the bracket 18 may be madein the form shown in either Figs. 7 or 8. v

A yoke 19 is provided with a pair of transverse slots 20 one of whichengages the head of the guide rail 7, these slots being positioned oneach side of the horizontal. center of the bracket and extend atopposite angles so that the bracket may be reversed on the guide rail 7at will, depending, of course, upon the direction in which the convexsurfaces of the disks 1 extend. A. hell crank is pivotally mountedwithin the yoke 19 by means of a pin 22 extending through the arms ofthe yoke and the bearing of the bell crank. One arm 21a of the bellcrank 21 is provided with a bifurcated end 23 which receives one end ofan eye bolt- 24, the ends being pivotally secured together by means of apin 25. This eye bolt 2-1 extends through a slot 26 provided in anextension 27 formed integrally with the yoke 19 and a Washer 23 engagesthe extension 27 and acts as a seat for the spring 29 disposed upon thel idy of the eye bolt 24. The opposite end of the bolt 24 is screwthreaded and receives a wing nut 30 which engages with the end of tiespring 29 the turning of the wing nut o adjusting the tension of thespring 29.

The other arm 21b of the bell crank 21 is formed to receive the cuttingtool 31. This cutting tool 31 is seated in a semi-circular groove 32which is formed on the inner side of the arm and extends throughout thelength. An eye bolt 33 is provided with a squared opening 34: whichreceives the cutting tool 31, the body of the eye bolt 33 extendingthrough a slotted opening 35 in the arm of the bell crank 21transversely of the slot 32. The opposite end of the eye bolt isprovided with screw threads 36 which receive a wing nut 37, thetightening of which secures the cutting tool 31 within the groove 32.The outer surface of the arm 21?) of the bell crank 21, adjacent theslot 35, is provided with diverging tapered surfaces 39 and a washer 38is interposed between the tapered surfaces 39 and the Wing nut 37. Uponthe tightening of the wing nut 37 the washer 38 may be brought intocontact with either of the tapered surfaces 39 which thereby dc- T?termines the angular position of the cutting tool 31, this angularposition depending upon the direction in which the convex surfaces ofthe disks 1 extend. The slot 32 extends throughout the inner surface ofthe arm 21?) of the bell crank 21 so that the cutting tool 31 may beshifted longitudinally to utilize the entire cutting surface thereof.

It is sometimes desirable to construct a supporting arm such asindicated at 8 which will prevent accidental longitudinal movement ofthe same, after it has once been properly located and secured withrespect to the guide rail 7. Two constructions are shown clearly inFigs.7 and 8 wherein, in Fig. 7, the supporting arm 8 is formed of a Tsection with the head of the section extending downwardly. This Tsection slidably receives a bracket 40 provided with a T shaped slotadapted to engage the head of the sup- P porting arm 8 and is secured inan adjustable position by means of a set screw 11. A U- shaped portionl2 substantially surrounds the hub 3 and is integrally formed with thebracket 40, the depending arms of the U- aped po tion. 41-2 ex end ng:Ear enough downwardly beyond the horizontal center of the. hub 3toprevent longitudinal movement of the bracket when once secured. i theproper position. i

In F 8 the supporting arm 8 is formed of a T section and has slidablymounted thereon a pair of brackets 43 provided with T shaped slotsadapted to engage the head of the supporting arm 8. These brackets 43are secured in the desired position by means of set screws 44 and thebrackets are provided with converging, depending arn1s45 which. projectdownwardly substantially below the hub 3 and inolose proximity thereto.This construction also prevents appreciable longitudinal movement of thesupporting arm 8 so that the T rail 7 when once? properly located ismaintained in this proper position.

It sometimes further desirable to employ a grinder in preference to thecutter 31 which has been heretofore described. This modification isclearly disclosed in Figs. 9 and 10. The constructionof the yoke and itsassociated parts are substantially the same as the yoke 19 heretoforedescribed except that the tool holder arm 21]) of the bell crank 21 isomitted and the arm 46 substituted therefor. This arm 46 forms one armof the bell crank 21 and is provided with ahead or enlarged circularportion 47 which has a central bore i8. A bushing 49 closed at one endis positioned in the opening 48 and frictionally secured therein andpositioned by means of an annular flange 50 engaging with the innersurface of the head 47. The grinding wheel 51 of proper diameter has acounterbore 52 in itsupper surface and acentral opening 53 extendsthrough the grinding wheel 51. This central opening 58 receives abushlng 54 and a stub shaft 55 is securely fastened to the under side ofthe grinding wheel 51'by means of a bolt 56 extending through thebushing 53 and into a centrally disposed screw threaded opening in theend of the stub shaft 55. The outside diameter of the stub shaft 55 isless than the inside of the diameter of the bushing 419, so that thestub shaft 55 may easily rotate within the bushing. A thrust-bearing orball 57 is pocketed within the end of the bushing d9 and engages withthe lower end'of the stub shaft 55 and functions to permit the grindingwheel 5.1 to freely rotate.

' F 6 clearly shows the relative position of the'various parts of thesupporting means and cutting device, the cutting device'being inengagement with one of the disks l of a gang. lVhen it is desirous tosharpen the 1 ing edge of the disks 1, referring particu arly to Fig. 1,the sharpening attachment 1' positioned as shown therein and the eyebolt carrying the cutter 31 is shifted radially downwardly onto thelower diverging portion'39 of the arm 216. This posi ons. t e cu ingedge of the utte 3 a a slight anglev with respect to the cutting edge 1is regulated through the tension spring 29, the tightening of the wingnut 30 increasing the tension of the cutter 81 on the disk 1 and theunscrewing or loosening of the wing nut 30 releasing the tens on on. thesprlng 29and Su sequently affecting the tension between the cutter 31and the disk 1. When one of the disks '1 has been sharpened and it isdesirous to sharpen the adjacent disk or any otherdisk in the'gang, thewing nut 30 is loosened to an extent to permit the washer 28, around theeye bolt 23, to be swung beyond the end of the extension 27 and out ofthe slot 26. This permits the sharpening device-to be positioned asindicated in 5 and slid along the guiderail 7 passing the V outerperipheries of the. disks 1 which is indicated by line A-A of Fig. 5.Vvllel the sharpening device has been moved along the guide rail-7 to aposition adjacent the-disk to be sharpenedthe eye bolt 28 is swung backinto the'slot 26' of the extension 27 andjthe washer 28 is again adaptedto engage the rear surface of the extension '27. This positions thecutter 3,1 in substantially the same position as indicated in Fig. 2 andthe tension of the cutter 31 against the disks 1' can be adjusted bymeans of the wing nut 30 as has been heretofore. described.

The positioning and the adjustment of the grinding Wheel 51 and thetension of the grinding wheel 51 against the disk 1 is regulated in, thesame manner as has been heretofore described. The tension of thegrinding wheel 51 against the cutting edge of the disk lis increased byturning the 'wing nut 30 downwardly thereby increasing tension of thesprings 29. and to. relieve the tension be-.

tween the grinding wheel 51-and the disk 1 thedirection of rotationofthe wing nutls reversed. The sharpening device is adjusted from onedisk'to another inthe same fashion as that. described with respect toFig. 5.

disks of the adjacent gang where the disks are arranged oppositely to.those shown in i ine o h k h iroi on sa g of- Fig. 6, it is necessary toremove the yoke 19 from the guide rail 7 and to support the yoke 19 onthe opposite rail and from the opposite slot 20 of the yoke. It shouldbe noted that this reverses the position of the cutting edge on the diskand in order to attain the proper shearing cut the wing nut 37 isloosened and the eye bolt 33 is swung laterally so that the washer 38engages the oppposite diverging surface 39 thereby swinging the cutter31 around until the proper edge engages with the cutting surface of thedisk 1. It is also necessary to remove the set screw 58 which securedthe yoke 19 to the guide rail 7 as shown in Fig. 1 and to place it inthe screw threaded opening directly opposite thereto thereby securingthe sharpening device in its reversed position on the rail 7 of theadjacent gang.

Having thus described my invention, what I claim is:

1. A. sharpening attachment for disk harrows comprising a guide barextending transversely of the disks, means for adjustably mounting saidguide bar on a portion of a harrow, a supporting member adjustablymounted on said guide bar and provided with a p votal tool holder, 3.cutting tool mounted for angular adjustment around its longitudinal axisin said tool holder and adapted to engage a disk to sharpen the same,and a tension regulating device engaging the supporting member and thetool holder to maintain the proper tension between the cutting tool andthe disk.

9.. A sharpening attachment for disk harrows comprising a guide baradapted to be mounted on a portion of the harrow and extending at rightangles to the disks, means for adjusting said guide bar with. respect tothe peripheries of said disks. a supporting member slidably mounted onsaid guide bar. said member having a pivotal tool holder. a cutting tooladjustably mounted in said tool holder and adapted to engage the. diskto sharpen the same, and pressure exerting means attached to thesupporting member and the tool holder for creating pressure of thecutting tool on said disk.

3. A sharpening device. for disk harrows comprising a voke provided witha groove adapted to slidably engage a portion of said harrow. extendingaXiallv along the disk gang a pivoted tool holder secured to said yoke,cutting means carried by the said tool holder. and a tension meansattached to the yoke and the tool holder.

4. A, sharpening device for disk barrows comprising a yoke provided withoppositely disposed grooves adapted to slidably en re a portion of saidharrow, a bell. crank nivo. to the yoke. one arm serving tool. holder, acuttin g tool adj ustably mounted in sa d arm, and a tension springattached to the other arm of the bell crank and to a portion of theyoke.

5. A sharpening device for disk harrows comprising a yoke provided witha pair of oppositely disposed grooves, adapted to slid ably engage aportion of said harrow, a bell crank pivoted to the yoke, one armserving as a tool holder, a cutting tool mounted in said arm and adaptedfor angular movement, a bolt pivotally secured to the end of theopposite arm of the bell crank having the other end removably engagingthe yoke, a spring surrounding the bolt and engaging the yoke, and ameans engaging the bolt for adjusting the tension of the spring.

6. A sharpening device for disk barrows comprising a yoke provided witha pair of oppositely disposed grooves for positioning the device withrespect to the disks, :1 cuter holder pivoted to the yoke, a tension adjLating device mounted between the yoke and the cutter holder, a cuttingtool mounted for longitudinal adjustment in the cutter holder, and meansfor angularly adjusting the cutting tool for properly positioning thetool with respect to the disk.

A sharpening device for disk barrows comprising a yoke provided iv'th apair or" oppositely disposed grooves for positioning the device withrespect to t the no edge of disk to be sharpened, a cut 'er holderpivoted to the yoke, a tension device attached to the yoke and thecutter holder, a cutting tool mounted in the cutter holder, and means fr angularly adjusting the cutting tool so as to effect a shear cut onthe edge of the disk as it rotates, the adjustment dependint upon theslot from which the device is suspended.

8. A sharpening attachment for disk harrows comprising a yoke providedwith transverse grooves adapted to slid-ably eng a portion of saidbarrow, a tool supper mg member pivotally mounted in said yoke, acutting tool carried by said member and adjustable angularly, resilientmeans cooperating with said cutting tool, and adjustable means forvarying the tension between the cutting tool and the disk.

9. A sharpening attachment for cisk harrows comprising a yoke providedwith. tran verse grooves disposed on opposite sides ct the horizontalcenter adapt d to slidahly engage a portion of said harrow. a tool supporting member pivotally mounted in said yoke, a sharpening tool carriedby said m mber and adapted for longitudinal and an lar adjustment, andresilient means for cre" ing tension between the cutting tool and thedisk.

10. A sh arpening attachment for disk harrows comprising a yoke providedwith oppositely disposed grooves extending angula ly with respect to thehorizontal center thereof, adapted to slidably engage a portion of saidbarrow, a tool supporting member pivoted within said yoke, a sharpeningtool longitudinally mounted in said member, means for angularlyadjusting the sharpening tool, and an adjustable tension means securedto the tool supporting member and engaging said yoke for varying thetension between the sharpening tool and the disk.

11. A sharpening attachment for disk harrows comprising a guide bar,adjustable means secured to the guide bar and to a portion between thedisks for positioning the guide bar with respect to the periphery of thedisks, adjustable means attached to the first mentioned means and to aportion of the harrow for supporting the guide bar, a supporting memberslidab-ly mounted on the guide bar, a tool holder in the form of a bellcrank pivoted at its central portion to the supporting member, a recessformed in one arm of the tool holder, a cutting tool longi tudinallymounted in said recess, said tool being secured in position by means ofan eye bolt through which the cutting tool extends,

, the body of the bolt being mounted for angular adjustment in the armand means attached to the opposite arm of the bell crank adapted toengage a portion of the supporting member for adjusting the tension,between the cutter and the disk.

12. A sharpening device for disk harrows comprising a. guide bar adaptedto be attached to said harro-w, a yoke provided with oppositely disposedgrooves suspended from said guide bar depending upon the direction inwhich the convex surface of the disks extend, means for locking the yoketo the guide bar, a tool holder pivotally mounted in said yoke providedwith a longitudinal groove adapted to receive and support a. cuttingtool, a cutting tool positioned in said slotand extending through anopening in an eye bolt, the opening substantially conforming to thecross section of the cutter, and the body of the eye bolt extendingthrough an opening transversely of said groove, and adapted for angularadjustment, and means attached to the opposite portion of the toolholder engaging a portion of the yoke, said means being provided with aresilient member for regulating the tension between the cutter and thedisk. V

In testimony whereof, I hereunto aifix my signature.

FRANCIS M. CASE.

